RESUMO
Today, due to the modern industrial life of human beings, stress has become prevalent among them and they will suffer from its complications. Exposure to stress during pregnancy can change many babies' normal physiological processes. The separate and combined effects of three common types of prenatal stress were investigated on motor learning of male offspring of rats. In the present study, pregnant NMRI rats were used. Except the control group, the other groups were stressed on the eighth day of gestation for 10 days. The motor learning of 40 male offspring rats were tested using the rotarod performance test 75 days after the experiment. The length of time that each rat could maintain its balance was recorded automatically. The study groups included control, electromagnetic field stress [intensity 1.2 mT, 50 Hz], immobility stress [for 0.5 hour - 2 times/day], social stress [6 rats kept in a small cage], and combined stress [all 3 of the above stresses]. Data were analyzed by using multiple comparisons and Tukey's tests. The motor balance of the combined stress group was lower than the control, at first timing of the first test day [P < 0.05]. In the next few days of the test, the effects of stress on learning of experimental groups were not similar. Combined stress reduced motor learning. Learning fluctuations were higher in electromagnetic field stress group compared to the other groups. The results of our study showed that prenatal combined stress can reduce motor learning of children
RESUMO
Background and Purpose: Ducrosiaanethifolia is an aromatic medicinal plant native to Iran, and has been used in traditional medicine for controlling infection, reducing anxiety and pain. Since analgesic effect of this plant has not been studied experimentally, the aim of the present research is investigating the analgesic effect of Dc. essential oil.
Materials and Methods: In this experimental study, 48 adult Wistar male rats were examined. Rats were divided randomly into 6 groups [n= 8] including: control group, morphine group and Dc. essential oil group [0.06, 0.125, 0.25 and 0.5 ml/kg, IP]. Antinociceptive effects of drugs were assessed using hot plate apparatus. The results were analyzed using SPSS using one-way analysis of variance [ANOVA] followed by post hoc Tukey. Differences were considered significant at p< 0.05.
Results: The Dc. essential oil [0.5 ml/kg] significantly decreased sensitivity to painin comparison with control group. Latency to onset of pain significantly increasedby the Dc. essential oil [0.125 ml/kg] 60 and 120 minutes after injection compared with control group. Also, the Dc. essential oil [0.25ml/kg] reduced pain 120 minutes after injection in comparison with control group.
Conclusion: Based on the findings of present study, the Dc. essential oil has analgesic properties and this plant can lead to decreased sensitivity to pain at some doses in the hot plate model of pain.
RESUMO
Introduction: It is well recognized that gender and race differences play a role in pain sensitivity, pain perception, response to analgesic drug and prevalence of certain chronic pain disorders. In this study investigated gender and strainrelated differences in the effect of food deprivation on formalin induced nociceptive behaviors in rats
Methods: This study was done in Qazvin University of Medical Sciences 8 groups of rats [220-300gr]. Groups 1 and 2: Effect formalin-induced nociceptive behaviours in male and female Sprague-Dawley rats. Groups 3 and 4: Effect formalin-induced nociceptive behaviours in male and female Wistar rats. Groups 5 and 6: Effect of food deprivation on formalin-induced nociceptive behaviours in male and female Sprague-Dawley rats. Groups 7 and 8: Effect of food deprivation on formalin-induced nociceptive behaviours in male and female Wistar rats. Food was withdrawn 48 h [short-term food deprivation] prior to performing the formalin test, but water continued to be available ad libitum. The formalin [50 microL, 2%] was injected into hind plantar paw. Immediately after the formalin injection, pain behaviors recorded for 90 minutes
Results: There is significant difference between male and female control Sprague-Dawley rats during phase 2B. Although interphase in male rats is more than female ones, but the phase 2B in female rats is more than male ones and phase 2 finished with delay in Sprague-Dawley race. There are no significant differences between male and female control Wistar rats during formalin test. Following 48-h food deprivation, male and femalerats exhibited enhanced nociceptive behaviors in response to formalin injection during phase 1, the interphase, phase 2. In contrast, 48 h food deprivation had significant effect on formalinevoked nociceptive behaviors in phase 2B for male Wistar and in interphase and phase 2B for female rats
Conclusion: The present study demonstrates the existence of gender and strain-related differences in rats in the development and maintenance of inflammatory hyperalgesia. Also, these differences observed following food deprivation